According to Variety “ Batman v Superman: Dawn of Justice ” is still the top contender at the box office, but its second weekend in theaters won’t be quite as victorious as its debut. Warner Bros. and DC’s clash of the superheroes is now tracking for a three-day total of $50 million, down from yesterday’s expected $58 million. “BvS” pulled in $15 million on Friday from 4,256 locations, and it’s expected to hit a cumulative domestic gross of $260 million by Sunday’s end. The first week of the movie took in $209.1 million in the U.S. — the 10th-highest first-week total of all time — with a $166 million opening weekend. Despite the negative reviews, audiences appear to have embraced the film, based both on box office turnout and on social media metrics. Fifty seven percent of the conversation on Twitter following the film’s debut has been positive, according to social media tracking service Fizziology. Less than 10 percent of the tweets about the film have been negative, with the r